At the time Fed chairman Ben Bernanke said that further reductions are set to take place throughout 2014 as the US economy recovers.

But Rosengren is no longer the Fed's black sheep. Today he told Reuters that he's "comfortable with the current approach that it looks like we're going to be following through on".

"Roughly a $10bn at each FOMC, if we were to gradually reduce purchases, I think that would be appropriate," Rosengren said. "I wouldn't want to take any dramatic steps at this stage because I don't think the economy warrants it."

The Fed announced that it would be reducing monthly asset purchases from $85bn to $75bn last month. Rosengren said that higher unemployment, would be a reason to halt QE tapering, while strong economic growth or an unexpected jump in inflation, would provide a case to accelerate reductions.